The incidence of carpal tunnel syndrome (CTS) is increasing within the industrial setting and is one of the most disabling and costly medical problems for companies, unions and/or employees. Attempts to minimize CTS in he workplace have included modifications in the working environment, redesigning of hand tools and alterations in work schedules. In addition to understanding these extrinsic risk factors, the intrinsic factors in the development of CTS such as diabetes mellitus, arthritis, wrist trauma, hormonal status, and hypothyroidism have been explored in groups of patients with CTS. Our preliminary work demonstrates an additional intrinsic risk factor, namely the association between carpal canal size and CTS. Other critical measurements, such as the depth, width, and shape of the canal may also be related to the development of CTS. The carpal canal area will be studied in a detailed cross-sectional approach in order to develop an understanding of which factors affect the compression of the median nerve. In this study, we intend to evaluate an entire group of workers who have been performing identical tasks within the same job setting. In this way we can control for work requiring hand/wrist movements. These workers will be given a battery of tests by a neurologist, including uniform clinical history, standardized physical examination, and electrodiagnostic studies. Following the administration of these tests, workers will be catergorized as those with and without CTS, and computerized tomography will be utilized to evaluate the size and shape of the carpal canal. It is hypothesized that these intrinsic risk factors associated with carpal canal size may play a role in the development of CTS in workers. In addition, the prevalence rate for CTS in this population of workers will be determined.